The Compton Gamma-Ray Observatory ( CGRO ) has observed the Cygnus region on several occasions since its launch in 1991 .
The data collected by the COMPTEL experiment on CGRO represent the most sensitive observations to date of Cygnus X-1 in the 0.75-30 MeV range .
A spectrum accumulated by COMPTEL over 10 weeks of observation time shows significant evidence for emission extending out to several MeV .
We have combined these data with contemporaneous data from both BATSE and OSSE to produce a broad-band \gamma -ray spectrum , corresponding to the low X-ray state of Cygnus X-1 , extending from 50 keV up to \sim 5 MeV .
Although there is no evidence for any broad line-like emissions in the MeV region , these data further confirm the presence of a hard tail at energies above several hundred keV .
In particular , the spectrum at MeV energies can be described as a power-law with a photon spectral index of \alpha = -3.2 , with no evidence for a cutoff at high energies .
For the 200 keV to 5 MeV spectrum , we provide a quantitative description of the underlying electron spectrum , in the context of a hybrid thermal/non-thermal model for the emission .
The electron spectrum can be described by a thermal Maxwellian with a temperature of kT _ { e } = 86 keV and a non-thermal power-law component with a spectral index of p _ { e } = 4.5 .
The spectral data presented here should provide a useful basis for further theoretical modeling .